The invention relates to a terminal block for connecting two sets of electrical conductors.
One common type of terminal block is formed by mounting individual connector units on a track or channel traversing the bottom of the connector units. This track is severable to yield terminal blocks with different numbers of connector units, as described by W. A. DeSmidt et al in U.S. Pat. No. 3,236,975. This track does not contribute to the function of holding the wire terminals on their individual bases, nor does it provide a longitudinal marker strip, which is a common feature in many electrical connectors. Additional parts and assembly steps are usually required to hold the wire terminals in place and provide a marker strip when individual connector units are used. While track-mounted connectors may be advantageous for some applications, an integral terminal block unit with multiple electrical connectors will provide advantages in manufacturing and assembly, by reducing the number of components and operations necessary to manufacture and assemble the terminal block.
For multiple unit terminal blocks, it is well known to place a market strip longitudinally across a plurality of individual connector units. As seen in E. J. Nielson et al, U.S. Pat. No. 3,293,593 and H. C. Curtis et al, U.S. Pat. No. 3,135,572, the marker strip must be manufactured and assembled separately from pieces which hold the wire terminal units in place. British Patent Specification 720,450, published Dec. 22, 1954 teaches that the marker strip assists in retaining wire terminal units in channels in the terminal block, but the British Patent Specification requires several additional parts to adequately retain the wire terminal units. In Eichwald, U.S. Pat. No. 2,258,750, a flat strip is shown which holds tube-shaped wire terminals to a flat base by means of bolts. Besides being unsuitable for use with screw-type wire terminals, this construction presents some inconvenience in holding all of the parts together during assembly. A simpler fastening means is desirable such as the one shown by Johnson in U.S. Pat. No. 2,221,710. Johnson uses abutments integrally formed with a pair of side walls to hold a flat wire terminal in place; however, the wire terminal must be inserted parallel to the receiving surface with the wire terminal screws partially unscrewed.
Many of the advantages of these prior art constructions can be obtained without the concomitant limitations of the prior art in a new, multiple connector, terminal block which requires fewer parts than most prior art assemblies and which is easier to manufacture and assemble.